Still No White Admirals (in NH or ME)
George DeWolf
I couldn't help but notice that Steve and Jane (Mirick) were at it again, with their White Admiral radars fully engaged—and still none have been found by them, or anyone else, in New Hampshire so far this season. I suspect the first one will appear soon, and they may yet emerge in some abundance as the season progresses. Let's hope so.
In an attempt to tempt fate and appeal to whatever forces in the natural world might conjure up the appearance of a very common butterfly that has thus far been conspicuously absent, I took a deeper dive into White Admiral observations on iNaturalist across the region—specifically Vermont, New Hampshire, Maine, and Canada—through June 8th over the past five years.
With butterfly observations down across the state, it does appear that the effects of last year's exceptionally wet spring are still being felt. Those conditions likely facilitated the spread of fungal and bacterial pathogens, while heavy rains may also have displaced eggs and caterpillars. Together, these factors seem to be continuing to affect butterfly populations throughout our region and may have had a disproportionate impact on one of New Hampshire's most frequently observed butterflies.
It is also important to remember that butterfly populations are inherently dynamic and can fluctuate dramatically from year to year. Weather patterns, disease, predation, parasitism, habitat conditions, and other environmental factors can cause populations to rise or fall substantially in a single season. As a result, a particularly good or bad year—or even two—does not necessarily indicate a long-term trend. Several years of observations are often needed to distinguish natural annual variation from genuine population increases or declines. I'm certain that this sort of analysis is above my pay grade.
Add to that the inherently opportunistic nature of iNaturalist observations, and we need to be careful not to read too much into the data. Still, it would be reassuring to see an upward trend in butterfly observations before long.
Here's a summary of what I found for research-grade observations of the White Admiral in northern New England and Canada through June 8 of each year:
To observe White Admiral observations for any of these years through June 8, click the appropriate year: 2022, 2023, 2024, 2025, 2026,
Please forgive my data-mining obsessiveness—it's an outgrowth of my former career in healthcare data analytics. Old habits die hard. 😎
George DeWolfWentworth, NH
John Calhoun
Mark Ellingwood
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amy highstrom
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Patricia Wood
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